Or anywhere else in Italy?
I went last month. Is there anything specific you're looking for?
phred, when you're going to Italy may make a very large difference. When are you going, and what are you concerned about?
We were in Rome in February (and other cities in Italy) I would call Rome slightly busy. Assisi was busier than what I expected. Rome churches, in particular, seemed a bit more busy than the last time we were in Rome. The important thing for us was to have restaurant reservations everywhere we wanted to eat. We didn't go to the coliseum. When we glanced into the forum it didn't seem that busy.
I would suggest following bloggers currently in Italy. The Catholic Traveler is one. Another is Romewise. Anecdotally, I heard a few comments that people stayed away due to the Jubilee, but there were fewer people than expected.
I was there a few weeks ago. Rome was not as crowded as Florence. The Vatican Museum was pretty crowded (the Sistine Chapel was pretty much shoulder to shoulder), as was the Colosseum. But I would say the crowds otherwise were pretty light at most of the other sites we visited. I am sure it will get busier leading up to Easter and I have no idea what the crowds will look like this summer.
I was there last month and it didn't feel crowded. We walked right into the Pantheon without pre-booking, for example.
I was in Rome for a week at the end of February. There didn’t seem to be above normal crowds.
We just returned yesterday from three weeks in Italy. Rome was busy but not like the crowds I've experienced in August/Sept. We did the Underground tour of the Colosseum so no crowds. The rest of the Colosseum was the typical shoulder to shoulder tourists. The Forum and Palatine Hill were a pleasure to wander through- busy but nothing crazy. Overall, it was busy in the usual places, but away from these it was delightful.